steviesj20
Need some opinions from you guys.
Background: I am a novice shade tree mechanic so be easy on me. I have a 1990 GW that I am using to tow my travel trailer. The 360 engine was rebuilt approximately 9,500 miles ago by a previous owner and has good oil pressure. I assume the pistons are stock. It has an Edelbrock cam, lifters, timing chain, intake, Howell tbi, stock manifolds, single 2.5" exhaust with Magnaflow cat/muffler. The engine is good for everyday driving but needs more power on the towing side. The hills are hurting me. I am running stock tires and 3:31 axle ratio. (I know the gears stink for towing but I need the best of both worlds).
I intend to put an Edelbrock efi system on the engine.
Should the cam be changed to something different?
Would you do something different to the cylinder heads?
Would shorty header help? I don't want the vehicle too noisy (wife) for highway use.
Please throw some opinions my way
Thanks!
tufcj
I really don't think you'll see much difference between the Howell and Edelbrock EFI systems as far as power. Shorty headers and a dual exhaust with an X or H pipe may help some. The Edelbrock cam is pretty good for towing.
The gears are your big problem for towing. Personally, I'd swap to about a 3.73 gear with stock tires for towing. With the other improvements, you shouldn't see much drop in mileage when not towing.
Bob
tufcj
Dusty
why change to the edelbrock EFI? there is a marginal gain at best if any over the Howell TBI and for your size motor and hp level what do you hope to gain?
An HEI distributor might help.
Your heads are fine dont change em there all pretty much the same unless you want a mild .5 compression jump then go source a set of ubber hard to find 291 heads with the small chambers
long tubes like doug thorleys would help more than shorties for torque. I like single 3" but single 2.5 cant be hurting you horribly.
how are you hurting? not enough rpms when kicking down to second gear? if so then the cam would be what i would be attacking. the performer cam is great for a cj with a 304, annemic for a 360 and down right wrong for a 401. so id be looking at a cam swap after fiddling around with some headers and maybe a new chip for the howell based on the new headers :-| IMHO the edelbrock is a marginal towing cam offering little gain over stock, the lift leaves alot to be desired
Gears like tuf said would be worth considering but that all depends on how everything else is designed.
what speed do you drive on the highway? what speed when towing? consider 65 mph as average cruising RPM 55 mph your towing speed.
31" stock tires and 3.31 gears your highway RPM
@ 45 mph is around 1700 rpm in direct and 2500 in second gear
@ 55 mph it is around 2100 rpm in direct and 3050 in second gear
@65 mph you cruise at 2500 and in second snap to 3600
31" stock tires and 3.73 gears your highway RPM
@ 45 mph is around 1950 rpm in direct and 2800rpm in second gear
@ 55 mph it is around 2350 rpm in direct and 3400 rpm in second gear
@65 mph you cruise at 2800 rpm and in second snap to 4050 rpm
Analyze those numbers and determine where your motor needs to make your peak torque. i always use my kick down point... second gear number for getting me close like my cherokee chief makes peak torque around 3800 but peak hp at 4800 but at 2400 which is my cruising rpm i still have 3/4 of my peak torque plenty of rpm for when i do openthe 4bbls and kick it down a gear.
the edelbrock cam in a 360 is probably peaked out with torque around 2200 rpm and all done rpm wise by 3800 so you are really limited when you do kick down into second gear by how much of the engine rpm and torque you will be able to use.
You arent driving a diesel with 800 ft/lbs torque so remember there are limitations to what a motor can and will do, designing things around the rpms you plan to use will yeild better results
1980_Cj7
How much experience do you have at towing? I'm not trying to be smart, it's just that I have found a trailer puts a tremendous drag on a tow vehicle. I'm always impressed/depressed at how much a trailer slows down even my 1 ton Chevy crew cab duallie with a 454, which is known to be a torque monster. This is especially true if you have hills in the mix. I'm just trying to save you from putting a lot of time, work, and money into an engine only to find out it didn't make much difference.
For instance, I thought my old Ford F250 with a 360 wasn't getting the job done, so I upgraded to the Chevy 454. I was shocked at the lack of difference there was between the two.
ironman_gq
you could always find a 401 and put your time and money in that and not have your vehicle down while you build the motor then it would be a simple 1day deal to swap the new motor over and be back on the road enjoying your new power :lo1l:
steviesj20
Well I certainly have done things wrong with this engine - I will admit this from the start - pee'd a lot of money away without knowing what I was doing.
What I don't like about the Howell tbi/cam setup is the crummy idle. I have even taken this rig up to Howell (great folks by the way) and we worked on it for several hours. Idle is not consistent. I attribute this to the 110 lobe center on the cam - seems like it confuses the computer at idle. This system has frustrated me.......
For reference I have a 86' J20 with a customefis tbi system and stock motor and of course lower gears. Truck runs awesome - should have come from the factory this way.
The trailer I tow is 22' long and about 4K loaded down with stuff.
We just got back from a week long trip through West Virginia and the hills are tough there. Two mountains had me down in 1st gear and accelerator matted to the floor.
On the interstate I towed from 55mph to 62 mph - 11 mpg and 8.5 in the mtns. Interstate grades weren't too bad but back roads killed the GW. Often crested in 2nd gear and 50 mph.
The GW has 29" tires (235/75/15).
I already own the Edelbrock system..... I'll be selling the Howell system in the future.
The ol' girl just seems to fall on her face at the slightest hint of a hill and higher rpms.
FuzzFace2
If you dont like the cam and think it the issue with the EIF then go for a good RV cam.
But as others have said change the gears to a min of 3.73
My 02 Durango I ordered with 3.92 just for towing my race car & trailer got to be pushing 5K and I have had to drop down to 2nd gear for some mnt. in PA across rt80. Yes I do have OD but pulling the trailer I don't even check MPG because I want to cry but would say 6-8 @65-75mph, flat down hill up hills it is just like the big rigs slow and steady.
To have a rig to tow and get good MPG both with & with out trailer not going to happen. Mine w/o trailer hiway I get 16mpg
but around town/hiway 10 - 12mpg even with OD.
Dave ----
JERSEYJOE
There is no replacement for displacement. Sell the 360 and do a 9 to 1 compression 401. I agree the Edelbrock cam is weaker than some of the others like the Crane and Engle grinds. With the 401 you will not believe the difference. I also agree chuck the gears and go 3.73
steviesj20
I understand that a lot of this issue is the gearing but at this point I want to concentrate on the receipe for pairing the correct camshaft with the efi system. I believe that if I can make the engine run efficiently (breath properly) that it will have sufficient enough power for what I want to do with it.
One thing I did do properly with this GW is to install an aluminum crossflow radiator. The Jeep ran no warmer than 205 degrees on the longest of hills. The remainder of the time the engine ran in the area it runs in with no load. Those radiators are really good! The Jeep has a 195 degree thermostat.
So given the parameters I have to work with - what would you change the camshaft to? I will need some torque and mix of high rpm to get over the hills.
Here is a link to another forum that you can see what I am pulling.
http://www.ifsja.org/forums/vb/showthread.php?t=92534
JERSEYJOE
I am also on the IFSJA froum.
I like the Engle Cam 5054 H grind. It's very similar to the old Sig Erson High Flow. This works well on a low compression 360 or 401.
ironman_gq
I also like the engle cams I put one in my 304 and it made a huge difference in my low end power. The cam I replaced was the clevite version of the performer cam. I had a roughe idle that I couldnt clear up and was lacking in low end. Call the guys at engle and tell them what you want and they will recommend a grind.
ironman_gq
did you have to mill the valve bosses for clearance or get different valve springs to run that cam to avoid coil bind or hitting the keepers on the valve boss?
JERSEYJOE
NO I used the 1971 401 heads with no problem. I also used Crane springs and retainers
steviesj20
I called Engle this afternoon.
The rep told me that the 5052 or 5054 as Jersey Joe mentioned would be ideal. They were polite with my novice questions.
He said the smaller 5052 would have little more power on the lower end where the 5054 would be a little better on the upper end. He said the Edelbrock timing chain and springs that I already have would be OK. I just need to tell them the lobe seperation and give them about 5 days to manufacture plus shipping time. Also need to degree the cam.
Seems like a flip of the coin.
I left a message with the bulltear answering machine seeking advice but had no return calls as of yet.
JERSEYJOE
Steve:
the 5054 is a great cam in a 8.5 to 1 401 motor. It has a relatively high lift and the profile is designed to fake the motor into thinking it has higher compression at lower RPM. When people talk about Dynamic Compression ration this is what they are talking about. My combination is running this cam at the 4 degree advance position. I am using an Edelbrock Performer intake, Edelbrock TES exhaust which is a bolt in for the stock exhaust manifolds and still runs a single exhaust. Mine is 2 1/2 all the way back. I am using a Holley Street Avenger Carb although the Edelbrock carb is OK for street use. This combination I have used before and it tows like night and day over the pathetic stock 360.
kris
JERSEYJOE wroteI am also on the IFSJA froum.
I like the Engle Cam 5054 H grind. It's very similar to the old Sig Erson High Flow. This works well on a low compression 360 or 401.
Joe and I have both pimped Engle here before. I just happen to be close enough to them that I was in their shop on Tuesday. :t:
With Engle you dont need to settle for a straight grind. I have been running (for the last 9 years) a k52 intake / k54 exhaust grind and I love it. I picked up a new one last week (yes, in person) and ended up needing to go back this week for valvesprings. If you live in an area that sniffs your tailpipe this is a better cam. Chris at Engle suggested that the k54 was getting a bit long for a late model that was subject to checks. Mine passed fantastic with a newer cat last year and still passed ok with the older one.
Anyways, Im building another 360 right now that will go in next weekend. All stock except the cam/springs, balance, and decking the block to .005". At .030" over, this combo puts the compression ratio at 8.5:1 and the "Dynamic" compression ratio at 7.2:1.
Their cams are ground to order and parkerised in house. They only dip cams once a week which is why it can take a few days to ship.
k.
JERSEYJOE
Thanks Kris.. I am not in the habit of " pimpin" anyone but I just report the success or failure that I have. Our sport needs good people like MC at Bulltear and companies like Engle that take the time to listen to their customers and discuss their needs.
ironman_gq
Engle are great! Im running in the straight up position but might want to play around with the 4 degree advanced position and see if it gives me any more low end :lo1l:
JERSEYJOE
I have found that most time they do run etter that way. Most of the aftermarket cams that I have ever checked needed at least 2 degrees just to get them to zero.
steviesj20
I believe that when I spoke with Engle last week that I spoke with a gentleman by the name of Doug.
Do you guys know if there is anyone in particular there that I should have spoken with?
I went over to the forum page on Edelbrock's website and posted a question about cam selection. I listed the following cam's.
Engle K52, K54, Summit K8600 and Crane H-260-2
Here is their reply:
"Any of those will work. Just remember that in general, the more duration at 0.050" you have, the less vacuum the engine will pull at idle and the higher your torque peak will be. 112 is good for the lobe separation. We usually recommend not going any lower than that."
Here is the link:
http://forums.edelbrock.com/forums/showthread.php?t=271
So with the comments I get from Edelbrock it looks like the cam with that will peak with highest torque rpm is the K8600. It seems like that is what I want for towing.
Right/Wrong??? Is my thinking correct on this?
